WorldCom given until Monday to come up with answers
US regulators have given WorldCom until Monday to provide details of how £2.5 billion of expenses were hidden from shareholders.
The Mississippi-based telecoms group has admitted that the money was wrongly listed as capital expenses in 2001 and 2002.
This means America's second-biggest long-distance telephone provider may have lost millions of pounds while declaring profits.
The Securities and Exchange Commission has filed civil fraud charges and given the company until Monday morning to file a detailed report on the "circumstances and specifics of these matters".
President George W Bush, citing concerns over sliding public confidence in corporate America, said the company's conduct had been 'outrageous'.
In Mississippi, Attorney General Mike Moore said officials had established a task force "to find out who is responsible for cooking the WorldCom books".
Former chief executive Bernie Ebbers, former chief financial officer Scott Sullivan and WorldCom's former accountant, Arthur Andersen, have all been ordered to preserve any company documents.
Andersen was convicted of obstructing justice for shredding documents in the case of Enron - the energy trader that went bankrupt after hiding losses through shady accounting.
WorldCom chief executive John Sidgmore has described this week's events as "an undeniable setback" for the company.
But he has said he plans to press ahead with plans to make the company leaner and simpler, starting by cutting up to 17,000 staff - beginning today.
